本文選題：嗎啡　切入點：條件性位置偏愛　出處：《寧波大學》2012年碩士論文

【摘要】：目的：藥物成癮是一種以復吸或強迫用藥為特征的慢性、反復發(fā)作的腦病。海洛因、甲基苯丙胺、可卡因等精神活性物質作用于大腦產(chǎn)生結構和功能性適應的結果從而使機體對毒品和環(huán)境產(chǎn)生異常的聯(lián)系，當再次暴露于伴藥線索時可以產(chǎn)生對濫用藥物的渴求。復吸是成癮的重要特征、也是治療成癮的關鍵問題。本課題主要通過向島葉核團給藥來觀察M型受體及其亞型的激動劑或拮抗劑在嗎啡獎賞機制中的作用，以期加深對成癮復吸的認識，為防治阿片類物質成癮戒斷后復吸提供理論參考。 方法：建立SD大鼠嗎啡條件性位置偏愛（conditioned place preference，CPP）模型，以訓練箱體頂部的LED圖案和底部的不同結構的地板作為辨別和條件性刺激信號，采用劑量遞增法對各組大鼠進行CPP訓練。 前測階段：腦定位手術7d后，將大鼠放入CPP實驗箱中，打開中間隔板，讓其自由穿梭15min并記錄大鼠在CPP箱兩側停留的時間，作為淘汰和分組的依據(jù)。 訓練階段：前測后的d2，抽掉中間隔板，條件位置性偏愛實驗采用非偏的實驗設計方案。訓練周期為6d，嗎啡的初始劑量為5mg kg~(-1)，每2d遞增5mg kg~(-1)，終劑量為15mg kg~(-1)。每天為一個訓練周期，，每只大鼠上下午各訓練1次。各組大鼠每天上午（或下午）給嗎啡，在CPP箱伴藥圖案側停留45min；下午（或上午）給生理鹽水在CPP箱非伴藥圖案側停留45min。若上午注射嗎啡，下午則注射生理鹽水；次日上午則注射生理鹽水，下午注射嗎啡，依此類推，交替進行。 測試階段：CPP測試在條件性訓練完成后次日（訓練開始后的d7）上午進行。將大鼠放在CPP箱內，抽取中間隔板允許大鼠在CPP箱體三個小室間自由探索15min，并記錄大鼠在兩側小室停留的時間。5h后我們向大鼠島葉區(qū)微注射藥物或者生理鹽水，5min后再次將大鼠放入CPP箱中進行測試15min。24h后對嗎啡依賴大鼠再次進行CPP測試，來觀察大鼠腦部微注射藥物后CPP的恢復情況。 覓藥行為的消退階段：動物建立嗎啡CPP行為3d后開始進行消退訓練，每隔3d將大鼠放入CPP箱內15min，待測試大鼠在每側箱體停留的時間基本相同（即CPP得分值基本在零左右）為消退試驗標準。 點燃階段：消退訓練結束后的d2，各組大鼠均皮下給予5mg/kg的嗎啡，10min后向大鼠島葉區(qū)兩側分別微注射0.5μL藥物或生理鹽水，5min后進行CPP測試。 CPP作為研究藥物依賴性和獎賞效應的行為藥理學模型之一，具有設備要求簡單，訓練周期短等優(yōu)點，因此在實驗中我們選取了CPP作為實驗大鼠的訓練模型并借用M型受體非選擇性抑制劑東莨菪堿來考察M型受體在島葉中的作用，接下來我們選取了M1受體拮抗劑哌侖西平，M2受體拮抗劑美曲他明，M3受體拮抗劑4-DAMP，M4受體拮抗劑托吡卡胺，M1受體激動劑MCN-A-343，M4受體激動劑LY2033298分別向大鼠島葉內進行微注射，進而觀察各組大鼠CPP的表達情況，從而來研究M型受體亞型在島葉中的作用，接下來我們通過在點燃階段向大鼠島葉區(qū)微注射M型受體非選擇性抑制劑東莨菪堿，M1受體拮抗劑哌侖西平，M2受體拮抗劑美曲他明，M3受體拮抗劑4-DAMP，M4受體拮抗劑托吡卡胺，來研究島葉內M型受體及其亞型對低劑量嗎啡點燃大鼠CPP的表達的影響。 結果： 1.島葉內微注射東莨菪堿對嗎啡依賴大鼠CPP表達的作用 島葉-東莨菪堿組CPP的得分值明顯低于島葉-生理鹽水組(P 0.05)，結果表明島葉內微注射東莨菪堿能夠顯著抑制嗎啡依賴大鼠CPP的表達。 2.島葉內微注射東莨菪堿對低劑量嗎啡點燃大鼠CPP表達的作用 東莨菪堿組CPP的得分值明顯低于生理鹽水組(P 0.05)，結果表明島葉內微注射東莨菪堿能夠顯著抑制低劑量嗎啡點燃大鼠CPP的表達。 3.島葉內微注射M1-M4受體拮抗劑后對嗎啡依賴大鼠CPP表達的作用 M1-pirenzepine組CPP得分值明顯低于生理鹽水組(P 0.01)，M4-tropicamide組CPP得分值則顯著高于生理鹽水組(P 0.05)。結果表明島葉內微注射M1受體拮抗劑哌侖西平后能顯著抑制嗎啡依賴大鼠CPP的表達，而島葉內微注射M4受體拮抗劑托吡卡胺則能促進嗎啡依賴大鼠CPP的表達。 4.島葉內微注射M1-M4受體拮抗劑對低劑量嗎啡點燃大鼠CPP表達的作用 M1-pirenzepine組CPP得分值明顯低于生理鹽水組(P 0.01)，在低劑量嗎啡點燃大鼠CPP表達恢復階段，M2-methoctramin組CPP得分值明顯低于生理鹽水組(P 0.05)。結果表明島葉內微注射M1受體拮抗劑哌侖西平后能顯著抑制嗎啡點燃大鼠CPP的表達。M2受體拮抗劑美曲他明在島葉內對戒斷后低劑量嗎啡點燃大鼠CPP的恢復有一定的抑制效果。 5.島葉內微注射M1、M4受體激動劑對嗎啡依賴大鼠CPP表達的作用 M1-MCN-A-343組CPP得分值明顯高于生理鹽水組(P 0.05)，M4-LY2033298組CPP得分值明顯低于生理鹽水組(P 0.01)。結果表明島葉內微注射M1受體激動劑MCN-A-343后能顯著促進嗎啡依賴大鼠CPP的表達，而M4受體激動劑LY2033298在島葉內則能抑制嗎啡依賴大鼠CPP的表達。 結論：M1型受體在島葉中可能起促進嗎啡依賴大鼠CPP表達的作用，而M4型受體在島葉中可能對大鼠CPP的表達起抑制作用，M2型受體在島葉中可能對低劑量嗎啡點燃大鼠戒斷后鞏固記憶的形成產(chǎn)生影響。
[Abstract]:Objective: drug addiction is a relapse or forced medication characterized by chronic, recurrent encephalopathy. Heroin, methamphetamine, cocaine and other psychoactive substances in the brain structure and functional adaptation results so that the body produces abnormal contact of drugs and environment, when exposed to drugs with clues can produce drug abuse craving. Relapse is an important feature of addiction, it is also a key problem in treating addiction. This subject mainly through to the insular nuclei administration to observe M receptor agonists or antagonists in morphine reward mechanism, in order to deepen our understanding of the complex addiction suction, to provide a theoretical reference for the prevention and treatment of opioid addiction and relapse after withdrawal.
Methods: a morphine conditioned place preference (conditioned place preference (CPP)) model was established in SD rats. The LED pattern on the top of the box and floor with different floors at the bottom were used as discriminating and conditioned stimulus signals. CPP training was carried out in each group by dose increasing method.
In the pretest stage: after 7d, the rats were put into the CPP test chamber, and the middle spacer plates were opened, so that they could freely shuttle 15min and record the time for the rats to stay on both sides of the CPP box as the basis for elimination and grouping.
The training phase: pre-test and post D2, removed the middle partition, conditioned place preference experiment using non experimental design. The partial training cycle is 6D, the initial dose of morphine was 5mg kg~ (-1), each 2D increased 5mg (-1) kg~, the final dose of 15mg kg~ (-1) for a day. A training cycle, each rat on the afternoon of the 1 day of training. The rats (morning or afternoon) to morphine, medicine pattern with a CPP box side stay 45min; afternoon (or morning) to saline in the CPP box without drug side pattern for 45min. morning afternoon if the injection of morphine, injection of physiological the next morning, saline; injection of saline, morphine and so on, the afternoon, alternately.
Test phase: CPP test in the conditional after training (training the next day after the start of the morning D7). The rats were placed in the CPP box, the middle partition selected rats were allowed free exploration 15min in the CPP box three chambers, and recorded the rats on both sides of the chamber residence time after.5h I have to insular area rat microinjection of drugs or saline, 5min again after the rats were placed in the CPP box to test 15min.24h on morphine dependent rats CPP test again, to observe the rat brain after injection of CPP micro recovery.
The extinction stage of drug seeking behavior: after the establishment of morphine CPP behavior, 3D began to go out of training, and rats were put into CPP box every 3D. The time to stay in each side box of the rats was basically the same.
At the ignition stage: after the end of the training, rats in each group were given 5mg/kg morphine subcutaneously. After 10min, 0.5 L L or saline were injected on both sides of the insular area respectively, and CPP was tested after 5min.
One of the behavioral model CPP as research on drug dependence and reward effect, has the advantages of simple equipment, short training period, so in the experiment we chose CPP as the training model of experimental rats and M receptor type non selective inhibitor of scopolamine to investigate M receptor in the insula in the role, then we the M1 receptor antagonist of M2 receptor antagonist and Xiping, song he Ming, M3 receptor antagonist 4-DAMP and M4 receptor antagonist tropicamide, M1 receptor agonist MCN-A-343, M4 receptor agonist LY2033298 were micro injection into rats in insula, and observe the expression of CPP in rats, so as to to study the effect of M receptor subtypes in the insula, we lit stage to the insular region of rat microinjection of M receptor type non selective inhibitor of scopolamine, M1 receptor antagonist prazosin and the West Flat, M2 receptor antagonist song he Ming, M3 receptor antagonist 4-DAMP and M4 receptor antagonist tropicamide, to study the insula type M receptor and its subtypes in kindled rats and the expression of CPP effect on the low dose of morphine.
Result錛

本文編號：1662390